Thin wall plastic tubing has many uses including for over-wrapping product containers, typically bottles, in which products, for example personal hygiene, pharmaceutical or food products, are shipped. The plastic tubing may be applied as a label over a major portion of the container to identify the product and/or enhance the appearance of the container. In another form, the plastic tubing provides a tamper-evident band that covers the container cap and neck, serving to indicate whether the container has been opened after shipping. In many cases the plastic tubing is processed so as to be shrinkable by the application of heat after a cut length of tubing has been placed over the container, and thus the tubing conforms snugly to the contours of the container.
In any such form, the subject plastic tubing labels and tamper-evident bands are applied to product containers in manufacturing environments, therefore process speed, tubing length consistency and neatness of the cut edge are important factors.
Most known machines for the application of thin wall plastic tubing to containers employ a scissor-type double blade cutter or a guillotine-type single blade cutter. Another cutter type is described in U.S. Pat. No. 5,531,858 entitled “Shrinkable Label Inserting Machine” in which a plurality of blades is mounted circumferentially around a passage through which a thin wall plastic tube is conveyed. Each of the blades is mounted rotatably on a wheel that is in contact with a driven band, e.g. a belt or chain. When an appropriate length of tubing has moved through and extends beyond the passage, the band is rotated to cause the blades to swing in plural overlapping arcs, cutting the tubing.
Other cutting machines are described in U.S. Pat. Nos. 7,275,469 and 7,562,611, each entitled “Planetary tubing cutter” wherein a planetary tubing cutter provides a gearing assembly having a pair of ring gears and a number of pinions with a blade affixed to each pinion. The ring gears are parallel to one another and are individually driven. The pinions are rotatably mounted to a side surface of one ring gear and engage a sun gear assembled to the other ring gear. When the ring gears rotate at the same speed, the pinions and blades do not revolve around their respective axes, and when one ring gear rotates at a speed different from the other ring gear, the pinions and blades revolve about their respective axes, intercepting and cutting a tube passing through an axial passage through the ring gears.
A drawback of the above-described cutters is that they don't always provide for clean cuts with a minimum of marks or burrs. Other drawbacks of existing cutting machines include slow cutting speeds and excessive force needed to be exerted against a workpiece. It would therefore be desirable to provide an improved cutter making cleaner cuts with a minimum of marks and burrs at increased cutting speeds not requiring excessive force of the cutting blade against the workpiece being cut.